Tubes for carrying fluid are used in many applications in the health care industry. For example, most dental offices use water supplied to various dental appliances for rinsing and cleaning the patient's teeth during dental procedures. In general, water is supplied to the appliances through a panel-mounted connector which is plumbed to a source of water. The appliance generally has only a simple on-off control for opening and closing a valve located on the appliance. The rate of flow typically is controlled by means of a standard stemmed flow control valve attached somewhere in the fluid line, generally near the panel.
Such standard flow control valves generally are bulky and may be inconvenient to adjust. They also may be difficult to clean and sanitize.
The present invention is directed to a valve assembly for use with fluid flow conduits, or tubes. The rate of fluid flow through a tube attached to the valve assembly is controlled by shifting of a sleeve which is mounted on the assembly. When the sleeve is shifted to a shutoff position, all flow of fluid through the valve assembly is stopped. Shifting of the sleeve away from the shutoff position opens a fluid path through the valve, thereby permitting fluid to flow to downstream apparatus. The rate of fluid flow is increased or decreased by incremental shifting of the sleeve in the assembly. The sleeve is configured so that precise adjustment of the rate of fluid flow is possible.
A general object of the present invention is to provide a novel fluid flow control valve which is simple and inexpensive to construct, yet which provides smooth variation in fluid flow rates between full-off and full-on positions.
Another object of the invention is to provide such a novel fluid flow control valve which when operated in one direction produces gradual variation in fluid flow rate and when operated in another direction produces rapid variations in fluid flow rates.
The flow control assembly of one embodiment of the present invention utilizes a rotatable sleeve with a helical closure element formed on an inner wall of the sleeve. The sleeve is mounted over a body which is connected to a fluid source, and which includes fluid passageways for carrying fluid. When the sleeve is rotated into the shutoff position, the fluid passageway through the valve is completely occluded to prevent fluid flow through the valve assembly. As the sleeve is rotated away from its shutoff position the fluid path is opened gradually so that the rate of fluid flow increases as the valve is rotated.
In another embodiment of the invention a sleeve is mounted for shifting longitudinally along a valve body which includes fluid passages. The sleeve is threadedly connected to the body and has a valve closure element therein which is positioned to close the fluid passage when in its shutoff position and to allow fluid flow when in its open position. Rotation of the sleeve about the body causes the sleeve and closure element to shift gradually between the open and shutoff positions.
A dental appliance having a simple on-off valve may be attached to the present flow control assembly with a standard quick connect device.
The device allows the user to adjust the rate of fluid flow in a precise manner. In addition, the device is convenient to use, small, and easily cleaned and sanitized. Moreover, the valve assembly of the present invention may be utilized with any fluid, such as water or air.